I try to alert
string which is variable in express.get and do to res. I wanna get in alert this "I am working fetch".
Here my server.js
var express = require('express');
var app = express();
app.use(express.static(__dirname + '/publicServer'));
app.get('/fimlList', function(req, res) {
console.log('i receive a GET request');
var tryFetch = {myString: 'I am working fetch'};
res.json(tryFetch)
})
app.listen(3000);
console.log('Server running on port 3000');
my App.js
import React from 'react';
var IchBinForm = require('./IchBinForm');
var SortFilms = require('./SortFilms');
var SearchFilm = require('./SearchFilm');
var FilmShort = require('./FilmShort.js');
var FilmLong = require('./FilmLong.js');
var App = React.createClass({
getInitialState: function() {
return {
list: {}
},
componentWillMount: function(){
var fromServer = fetch('/fimlList')
.then(function(response) {
return response.json()
})
.then(function(responseJson) {
return responseJson.myString
})
alert(fromServer);
},
changeShow: function(newShow, filmId) {...},
deleteFilm: function(id) {...},
seeForChangeInForm: function(change, id) {...},
addNewFilm: function() {...},
sortMe:function() {...},
searchMe: function(searchWord) {...},
howSearch:function(whichCheckBox, val) {...},
render: function() {
....
}
}
});
return (...);
}
});
module.exports = App;
and what I get:
What do I do wrong ?
You assign fromServer
with a promise from fetch... You try to write code as it was synchronously while in fact it's asynchronously
Either move the code inside the last then
function
.then(function(responseJson) {
console.log(responseJson)
})
or use async/await to get a synchronously feeling while writing code
async function(){
var fromServer = await fetch('/fimlList')
.then(function(response) {
return response.json()
})
.then(function(responseJson) {
return responseJson.myString
})
alert(fromServer);
}
if you go by the async/await approach i would suggest something more like this:
async function(){
let response = await fetch('/fimlList')
let responseJson = await response.json()
let fromServer = responseJson.myString
alert(fromServer)
}
You're not consuming your promise , try :
componentWillMount: function(){
fetch('/fimlList')
.then(function(response) {
return response.json()
})
.then(function(responseJson) {
alert(responseJson.myString);
})
},
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